Command line options

The following command line options must be specified when TSMP-PDAF is executed:

n_modeltasks

n_modeltasks (integer) Number of realisations. Must be equal to [DA] nreal.

Note that both n_modeltasks (or nreal) and the total number of MPI tasks specified, f.e. with srun -n or mpiexec -np (internally: npes_world) have to match with the total number of processes specified for the component models: PF:nprocs, CLM:nprocs, COSMO:nprocs.

filtertype

filtertype (integer) Type of filter used for data assimilation. For more details see the PDAF documentation. Currently, the following filter options are available

(Ensemble Kalman Filter(Enkf)) is supported.
(Ensemble Transform Kalman Filter(Etkf)) is supported.
(Local Ensemble Transform Kalman Filter(Letkf)) is supported.
(Error Subspace Transform Kalman Filter(Estkf)) is supported.
(Local Error Subspace Transform Kalman Filter(Lestkf)) is supported.
(Local Ensemble Kalman Filter(LEnkf)) is supported.

To see all available command line options for the different filter algorithms please refer to PDAF wiki link

http://pdaf.awi.de/trac/wiki/AvailableOptionsforInitPDAF

subtype

subtype (integer) Parameter subtype, different options for each filter. See Command Line Examples.

obs_filename

obs_filename (string) Prefix for observation files.

Note: The prefix for observation files cannot be longer than 100 characters! Otherwise, the observation filename will be cropped. In these cases, usually an error message No such file or directory is thrown in next_observation_pdaf.F90.

rms_obs

rms_obs (real) Measurement error. This is the standard deviation of the Gaussian probability distribution of the observations.

rms_obs should be given in units of the observation.

delt_obs

delt_obs (integer) Number of data assimilation intervals (see [DA]da_interval) that are forward computed, before assimilation is actually performed.

In general, delt_obs should be as small as possible, in order to avoid performance loss. See remark in [DA]da_interval.

screen

screen (integer) Control verbosity of PDAF

0: no outputs
1: basic output (default)
2: 1 plus timing output
3: 2 plus debug output

Command Line Examples

Command Line Example: EnKF

subtype (integer) Parameter subtype for Ensemble Kalman Filter (EnKF).

Full ensemble integration; analysis for \(2\cdot \mathtt{dim\_obs} > \mathtt{dim\_ens}\)
Full ensemble integration; analysis for \(2\cdot \mathtt{dim\_obs} \leq \mathtt{dim\_ens}\)
Offline mode

Example of the model execution using EnKF analysis:

    mpiexec -np 512 ./tsmp-pdaf -n_modeltasks 64 -filtertype 2 -subytype 1 -delt_obs 1 -rms_obs 0.1 -obs_filename myobs

With this command, the TSMP-PDAF executable tsmp-pdaf will be run with 64 realisations (8 processors for each realisation) and EnKF analysis will be performed every assimilation cycle with an observation error of 0.1 and observations read from the files myobs.xxxxx.

Command Line Example: ETKF

subtype (integer) Parameter subtype for Ensemble Transform Kalman Filter (ETKF).

full ensemble integration; apply T-matrix analogously to SEIK
full ensemble integration; formulation without T matrix
Fixed error space basis; analysis with T-matrix
Fixed state covariance matrix; analysis with T-matrix
Offline mode; analysis with T-matrix

Example of the model execution using EtKF analysis:

    mpiexec -np 512 ./tsmp-pdaf -n_modeltasks 64 -filtertype 4 -subytype 1 -delt_obs 1 -rms_obs 0.1 -obs_filename myobs

With this command, the TSMP-PDAF executable tsmp-pdaf will be run with 64 realisations (8 processors for each realisation) and EtKF analysis will be performed every assimilation cycle with an observation error of 0.1 and observations read from the files myobs.xxxxx.

Command Line Example: ESTKF

subtype (integer) Parameter subtype for Error Subspace Transform Kalman Filter (ESTKF).

Standard implementation with ensemble integration
Fixed error space basis
Fixed state covariance matrix
Offline mode

Example of the model execution using EstKF analysis:

    mpiexec -np 512 ./tsmp-pdaf -n_modeltasks 64 -filtertype 6 -subytype 1 -delt_obs 1 -rms_obs 0.1 -obs_filename myobs

With this command, the TSMP-PDAF executable tsmp-pdaf will be run with 64 realisations (8 processors for each realisation) and EstKF analysis will be performed every assimilation cycle with an observation error of 0.1 and observations read from the files myobs.xxxxx.

Command Line Example: LETKF

cradius (deprecated: local_range) (real) set cut-off radius, 0.0 by default, any positive value should work.

locweight (integer) set weight function for localization, default=0 for constant weight of 1; possible are integer values 0 to 4.

subtype (integer) Parameter subtype for Local Ensemble Transform Kalman Filter (Letkf).

full ensemble integration; apply T-matrix analogously to SEIK
Fixed error space basis; analysis with T-matrix
Fixed state covariance matrix; analysis with T-matrix
Offline mode; analysis with T-matrix.

Example of the model execution using Letkf analysis:

    mpiexec -np 512 ./tsmp-pdaf -n_modeltasks 64 -filtertype 5 -cradius 3 -locweight 0 -subtype 0 -delt_obs 1 -rms_obs 0.1 -obs_filename myobs

With this command, the TSMP-PDAF executable tsmp-pdaf will be run with 64 realisations (8 processors for each realisation) and Letkf analysis will be performed every assimilation cycle with an observation error of 0.1 and observations read from the files myobs.xxxxx.

Command Line Example: LESTKF

cradius (deprecated: local_range) (real) set cut-off radius, 0.0 by default, any positive value should work.

locweight (integer) set weight function for localization, default=0 for constant weight of 1; possible are integer values 0 to 4.

subtype (integer) Parameter subtype for Local Error Subspace Transform Kalman Filter (LESTKF).

Standard implementation with ensemble integration
Fixed error space basis
Fixed state covariance matrix
Offline mode

Example of the model execution using Lestkf analysis:

    mpiexec -np 512 ./tsmp-pdaf -n_modeltasks 64 -filtertype 7 -cradius 3 -locweight 0 -subtype 0 -delt_obs 1 -rms_obs 0.1 -obs_filename myobs

With this command, the TSMP-PDAF executable tsmp-pdaf will be run with 64 realisations (8 processors for each realisation) and Lestkf analysis will be performed every assimilation cycle with an observation error of 0.1 and observations read from the files myobs.xxxxx.

Command Line Example: LENKF

cradius (deprecated: local_range) (real) set cut-off radius

0.0 by default
any positive value should work.

sradius (deprecated srange) (real): the support radius of the localization, default: equal to cradius. Usage in PDAF_local_weight.F90 (https://pdaf.awi.de/trac/wiki/PDAF_local_weight)

locweight == 0: sradius is not used
locweight == 1: sradius is distance with weight 1/e, for avoiding sharp cut-off, cradius should be significantly larger than sradius
locweight == 2: sradius is the support radius for 5th-order polynomial, can safely be chosen the same as cradius, parametrization change of the 5th-order polynomial is at sradius/2, see https://github.com/PDAF/PDAF/blob/ed631034956dece8e91e8b588c4cf3aaa7916f49/src/PDAF_local_weight.F90#L147-L176.

locweight (integer): set weight function for localization,

default=0
for constant weight of 1
possible are integer values 0 to 4.(see init_pdaf)

locweight == 0    ! Uniform (unit) weighting
locweight == 1    ! Exponential weighting
locweight == 2    ! 5th-order polynomial (Gaspari&Cohn, 1999)

subtype (integer) Parameter subtype for Localized Ensemble Kalman Filter (Lenkf).

Full ensemble integration; analysis with covariance localization
Offline mode

Example of the model execution using Lenkf analysis:

mpiexec -np 512 ./tsmp-pdaf -n_modeltasks 64 -filtertype 8 -cradius 3 -locweight 0 -subtype 0 -delt_obs 1 -rms_obs 0.1 -obs_filename myobs

With this command, the TSMP-PDAF executable tsmp-pdaf will be run with 64 realisations (8 processors for each realisation) and Lenkf analysis will be performed every assimilation cycle with an observation error of 0.1 and observations read from the files myobs.xxxxx.